title: Prediction of the energy required for extracorporeal shock wave lithotripsy of certain stones composition using simple radiology and computerized axial tomography.
abstract: OBJECTIVE
  To demonstrate that urinary lithiasis have a specific susceptibility to fracture through extracorporeal shock wave lithotripsy (ESWL), which is common for all calculi with the same composition and which can be estimated before treatment using CT or plain x-ray.
  
  
  METHODS
  We present an in vitro, prospective, randomized, blind and multi-centre study involving 308 urinary calculi. 193 of these met the inclusion criteria: whole calculi composed purely of calcium oxalate monohydrate (COM), uric acid (UA) or carbonate apatite (CA), or a mix of oxalate (COMix) and of a size greater than 0.5 cm. The samples were broken using lithotripsy until reaching a pre-established level of comminution. The variables employed were energy dose (Edose) per cm(3) of lithiasis and Edose adjusted to lithiasic surface (EdAJ) per cm(3).
  
  
  RESULTS
  COM was the hardest, requiring an Edose of 119,624 mJ/cm(3) and an EdAJ of 36,983 mJ/cm(3), followed by COMix (75,501/36,983), CA (22,734/21,186) and UA (22,580/6,837) (P < .05). Gmax y Gmda were correlated with Edose (r = 0.434/r = 0.420) and EdAJ (r = 0.599/r = 0.545) (P < .01). UH were correlated, in bone window and soft tissue window, with Edose/cm(3) (r = 0.478/r = 0.539) y EdAJ/cm(3) (r = 0.745/r = 0.758) (P < .01).
  
  
  CONCLUSIONS
  In our in vitro research lithiasis require, due to the specific nature of their composition, a given amount of energy in order to be broken by ESWL, which is inherent to all those sharing the same composition, and can be predicted using CT or plain x-ray.
authors.affiliation: Unidad de Gestión Clínica de Urología y Nefrología, Hospitales Universitarios Virgen del Rocío, Sevilla, España. Electronic address: earguelles@telefonica.net.
authors.forename: E
authors.initials: E
authors.lastname: Argüelles-Salido
authors.affiliation: Unidad de Gestión Clínica de Urología y Nefrología, Hospitales Universitarios Virgen del Rocío, Sevilla, España.
authors.forename: P
authors.initials: P
authors.lastname: Campoy-Martínez
authors.affiliation: Unidad de Gestión Clínica de Diagnóstico por la Imagen, Hospitales Universitarios Virgen del Rocío, Sevilla, España.
authors.forename: J
authors.initials: J
authors.lastname: Aguilar-García
authors.affiliation: Unidad de Gestión Clínica de Laboratorios Clínicos, Hospitales Universitarios Virgen del Rocío, Sevilla, España.
authors.forename: V
authors.initials: V
authors.lastname: Podio-Lora
authors.affiliation: Unidad de Gestión Clínica de Urología y Nefrología, Hospitales Universitarios Virgen del Rocío, Sevilla, España.
authors.forename: R
authors.initials: R
authors.lastname: Medina-López
mesh_terms: D011211:Electric Power Supplies; D006801:Humans; D007669:Kidney Calculi / Q000737:chemistry / Q000000981:diagnostic imaging* / Q000628:therapy*; D008096:Lithotripsy / Q000379:methods*; D011237:Predictive Value of Tests; D011446:Prospective Studies; D016037:Single-Blind Method; D014057:Tomography, X-Ray Computed
keywords: Composición; Composition; Extracorporeal shock wave lithotripsy; Lithiasis; Litiasis; Litotricia extracorpórea por ondas de choque; Ondas de choque; Radiology; Radiología; Shock wave; Tomografía; Tomography